Java 5

Class(name example:HelloWorld)

-reusable modules, create instances, filled with methods, provide your applet with methods
-serve as blueprints for the objects that programmers need to create

1. letters
2. numbers
3. underscores _
4. dollar signs $
5. case-seneitive, start with upper case letters

{
class definition or
a statement of a method ending with ; or
an assignment statement
(ex: x=0; )
(ex: a variable = the value to be put into the variable;)
}

For Example:

public class HelloWorld
{
class definition
}


Instance Variables
-the variables we want each instance to contain, to hold info



3 Types of Methods - usually is data type +method name
- declare a method is like declare a variable and declare a method
-it usually has data type+name


A. Mian Method

public static void main ( String [ ] args ) parameter list/arguments, providing outside info
{
statement1;
statement2;
}


B. Constructor Method

- in this kind of method, the method name is just like the class name
- to bulid a new object from a class
- to give its data elements the values

public HelloWorld (String text) parameter list/arguments, providing outside info
{
statement;
}


C. Method

public void printText () parameter list/arguments, providing outside info
{
statement;
}

void: When a method doesn't need to return a value, the type in its first line will be void.


2 ways of making comments

Type 1: Multi-line comment
/*
*/

Type 2: Single-line comment
//